Talked about this week

How a term is ranked

score = breadth × lift
breadth = blogs using the term this window / blogs publishing this window
lift = (breadth this window / typical breadth in a window-length slice of the baseline)
       / the same ratio for the median term

A term has to be at least two and a half times as broad as in a typical earlier window of the same length, measured against how much broader the median term reads (recent weeks are held more completely than older ones), and used by a floor of blogs rather than a handful, so an ordinary word drifting from one week to the next does not read as news. Function words, generic headline verbs and the calendar are dropped before counting: months and weekdays trend every week by definition. A source counts only if it published before the window opened, so a blog new to the corpus cannot read as a spike.